my next steps I'm planning are a duplex/quadplex build on land I'm buying from family with an existing single family home already on it. 

if you're looking at 1-4 unit properties, don't kill yourself trying to create an LLC just yet. find your lender first then see if they'll require you to close in an LLC or not. single-member LLCs do not provide as much legal protection as we would like to think, so if that's your reasoning for wanting to create one right off the bat, that's just something to consider. as far as a business license, AFTER you close on the property, call the town hall and ask if they want you to have one there bc you're collecting rent there. if you're using a PM company, they will probably say no. :)

We are open to multi and single family investments.

Hey Liad - Condos can pose some challenges mostly due to monthly association fees, limited control over the property, and potential for slower appreciation compared to single-family homes.

It's essential to check with the administrator of your husband's 401(k) plan to confirm eligibility criteria.Plan Rules: Each 401(k) plan has its own rules and regulations governing loan eligibility, loan amounts, repayment terms, and other aspects of borrowing from the account.

I would recommend buying new properties in single purpose LLCs - if you transfer them now you would trigger a transfer tax event unless you put them into a land trust. 

Quote from @Robert Rixer:  Have you heard of the installment method of income tax accounting.?

I'm currently living down here but all my financials (assets, bank accounts, income, tax filings, etc) are in the US.

House hack again or do a live in flip (if you are single and/or have spouse or partner that can take it).

Our current focus is working on 1-4 unit fix and flips, but eventually work towards being able to refinance properties and keep and cash flow them.My question is  tailored on the the way I should structure our relationship for the legal and tax base purposes.Should I secure the deals under my business and pay my partner out of my business operating account?